Commercial vegetable soups could have up to 50% less salt without changing liking

Salt levels may be reduced by up to 48% in commercial vegetable soups without affecting consumer liking, says a new study from Ireland.

Scientists report in Food Quality and Preference indicate that, while there may be significant differences in the ability of men and women to detect salt, this did not affect the liking of reduced salt soups.

“The addition of 0.15% rosemary or the addition of 0.1% lactoferrin hydrolysate are recommended as both ingredients increased acceptability scores up in line with the regular sodium commercial meal,” wrote researchers from Teagasc Food Research Centre, UCD, and the University of Limerick.

“Addition of either ingredient into the reduced sodium soups allowed for salt reductions of approximately 48% to be achieved without adversely affecting the sensory acceptability of the meals.

“However, if food manufacturers are to pursue this sodium reduction strategy they may need to accept minor insignificant reductions in consumer acceptability as a result.”

Reformulation pressures

The results of the study may only be applicable to vegetable soups, however. Campbell Soup, which hit the headlines last year
by re-introducing some sodium to a line of soups that had been subject to significant cuts, said a one-size-fits-all approach did not work.

For example, a sodium level of 480mg/serving for condensed tomato soup had been “well accepted by consumers and continues to be successful in the marketplace”, said the firm.

However, reducing sodium to 480mg in another product was not accepted by consumers. “We also re-launched a mainstream product line as Select Harvest soups at a uniform sodium level of 480 mg per serving, without making the healthy sodium level part of our consumer messaging, i.e. maintaining the mainstream product positioning of the line.

“This last move proved to be too aggressive and did not meet the expectations of consumers purchasing soups that are not explicitly positioned as ‘healthy’.

Vegetable-specific

The new data indicated that salt reductions up to 48% may be achievable. The researchers performed two sets of tests: The first was to measure if women and men had different salt taste thresholds using model salt-water solutions; and the second test analyzed the acceptability reduced salt soups (0.45% salt) compared to soup with regular commercial salt concentrations (0.93%).

The results from the first test indicated that women had lower salt detection limits to men.

Despite this difference, there were no differences between the genders when it came to acceptability or purchase intent scores of the reformulated reduced salt vegetable soups.

Including a blend of spices (rosemary, oregano and sage) significantly reduced the acceptability of the vegetable soup samples, with the exception of the reduced sodium soup alone which did not contain any extra ingredients.

“These results highlight the importance of acceptable taste characteristics on the decision to purchase or repurchase a food,” wrote the researchers.

“The inclusion of the consumer in the reformulation process of reduced salt foods was also shown to be a very effective service available to manufacturers in order to retain acceptable sensory scores.”

Salt/ sodium

The sodium in salt is thought to be a contributor to high blood pressure, which in turn has been linked to higher risk of heart attack and stroke, the United States’ leading causes of preventable death.

Although Americans consume nearly twice the recommended limit of salt each day, very little of the sodium in the national diet comes from saltshakers; an estimated 70 to 80% is added to foods before purchase. As a result, pressure on food manufacturers to slash the salt content of their products has grown.